This disclosure relates generally to equipment utilized and operations performed in conjunction with a subterranean well and, in an embodiment described herein, more particularly provides an isolation valve for use in drilling operations.
An isolation valve can be used in a drilling operation for various purposes, such as, to prevent a formation from being exposed to pressures in a wellbore above the valve, to allow a drill string to be tripped into and out of the wellbore conventionally, to prevent escape of fluids (e.g., gas, etc.) from the formation during tripping of the drill string, etc. Therefore, it will be appreciated that improvements are needed in the art of operating isolation valves in drilling operations. These improvements could be used in other types of well tools, also.